Air traffic management often utilizes predefined navigation corridors to direct aircraft through and/or around particular areas to ensure, for example, that the operation of the aircraft is in compliance with the guidelines of various authoritative administrations (e.g., the Federal Aviation Administration (FAA) and the International Civil Aviation Organization (ICAO)). One type of such navigation corridors are those defined by Required Navigation Performance (RNP). RNP requires that an aircraft must be able to navigate a chosen flight plan (e.g., an approach for landing) within a particular tolerance and alert the pilot when the tolerance is exceeded.
Modern aircraft often include various displays for simultaneously displaying several types of information to a user (e.g., the pilot). Primary flight displays (PFD) and head-up displays (HUDs) often that project various symbols and information over an image of the environment outside the aircraft. More specifically, primary flight displays typical make use of an artificial image of the environment (e.g., a digital terrain) while HUDs include a transparent display, or image combiner, through which the may views the exterior. In modern implementations of both, various “symbology” is rendered over the image of the exterior of the aircraft to indicate various operational conditions to the user. There is a need for a method and system for using such displays in such a way as to indicate to the user when the aircraft is deviating from its flight plan and/or is in danger of exiting a navigation corridor in which it is operating.
Accordingly, it is desirable to provide a method and system for operating a display device associated with an aircraft in such a way as to indicate to the user when the aircraft is within a particular proximity to a boundary of the navigation corridor while minimizing the amount of clutter on the display. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.